From db9c00ec1ec48e8adfed756fbbaf7ed37134d7ab Mon Sep 17 00:00:00 2001
From: Lunarmagpie <Bambolambo0@gmail.com>
Date: Thu, 22 Dec 2022 21:00:58 -0500
Subject: [PATCH 1/4] update docs to better explain -> operator

---
 crates/reporting/tests/test_reporting.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/crates/reporting/tests/test_reporting.rs b/crates/reporting/tests/test_reporting.rs
index da3db9af29..de74eaf394 100644
--- a/crates/reporting/tests/test_reporting.rs
+++ b/crates/reporting/tests/test_reporting.rs
@@ -5645,11 +5645,16 @@ All branches in an `if` must have the same type!
     5│          1 -> True
                   ^^
 
-    The arrow -> is only used to define cases in a `when`.
+    The arrow -> is used to define cases in a `when` expression:
 
         when color is
             Red -> "stop!"
             Green -> "go!"
+
+    And defining functions:
+
+        increment = \n -> n + 1
+
     "###
     );
 

From 3265a786a5300cdcb59c1b99385c628593366c42 Mon Sep 17 00:00:00 2001
From: Lunarmagpie <Bambolambo0@gmail.com>
Date: Fri, 23 Dec 2022 11:01:50 -0500
Subject: [PATCH 2/4] make changes suggested by folkertdev

---
 crates/reporting/src/error/parse.rs      | 6 ++++--
 crates/reporting/tests/test_reporting.rs | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/crates/reporting/src/error/parse.rs b/crates/reporting/src/error/parse.rs
index 2b4f33caf3..674ae02663 100644
--- a/crates/reporting/src/error/parse.rs
+++ b/crates/reporting/src/error/parse.rs
@@ -279,8 +279,8 @@ fn to_expr_report<'a>(
                                 alloc.reflow("The arrow "),
                                 alloc.parser_suggestion("->"),
                                 alloc.reflow(" is only used to define cases in a "),
-                                alloc.keyword("when"),
-                                alloc.reflow("."),
+                                alloc.keyword("`when`"),
+                                alloc.reflow("expression:"),
                             ]),
                             alloc
                                 .vcat(vec![
@@ -289,6 +289,8 @@ fn to_expr_report<'a>(
                                     alloc.text("Green -> \"go!\"").indent(4),
                                 ])
                                 .indent(4),
+                            alloc.reflow("And to define a function:"),
+                            alloc.reflow("increment = \\n -> n + 1").indent(4),
                         ])]
                     }
                 },
diff --git a/crates/reporting/tests/test_reporting.rs b/crates/reporting/tests/test_reporting.rs
index de74eaf394..b8524d110d 100644
--- a/crates/reporting/tests/test_reporting.rs
+++ b/crates/reporting/tests/test_reporting.rs
@@ -5651,7 +5651,7 @@ All branches in an `if` must have the same type!
             Red -> "stop!"
             Green -> "go!"
 
-    And defining functions:
+    And to define a function:
 
         increment = \n -> n + 1
 

From f932bb66a06559afab76870a5d1cd4a0e6f1adf7 Mon Sep 17 00:00:00 2001
From: Lunarmagpie <Bambolambo0@gmail.com>
Date: Fri, 23 Dec 2022 11:07:57 -0500
Subject: [PATCH 3/4] Add function binding to error message

---
 crates/reporting/src/error/parse.rs      | 5 ++++-
 crates/reporting/tests/test_reporting.rs | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/crates/reporting/src/error/parse.rs b/crates/reporting/src/error/parse.rs
index 674ae02663..e099dc87fc 100644
--- a/crates/reporting/src/error/parse.rs
+++ b/crates/reporting/src/error/parse.rs
@@ -290,7 +290,10 @@ fn to_expr_report<'a>(
                                 ])
                                 .indent(4),
                             alloc.reflow("And to define a function:"),
-                            alloc.reflow("increment = \\n -> n + 1").indent(4),
+                            alloc.vcat(vec![
+                                alloc.text("increment : I64 -> I64"),
+                                alloc.text("increment = \\n -> n + 1"),
+                            ]).indent(4)
                         ])]
                     }
                 },
diff --git a/crates/reporting/tests/test_reporting.rs b/crates/reporting/tests/test_reporting.rs
index b8524d110d..452b009380 100644
--- a/crates/reporting/tests/test_reporting.rs
+++ b/crates/reporting/tests/test_reporting.rs
@@ -5653,6 +5653,7 @@ All branches in an `if` must have the same type!
 
     And to define a function:
 
+        increment : I64 -> I64
         increment = \n -> n + 1
 
     "###

From 439befcc3808f00f2ae5af451ed688a0b1bbf80d Mon Sep 17 00:00:00 2001
From: Folkert <folkert@folkertdev.nl>
Date: Fri, 23 Dec 2022 17:19:54 +0100
Subject: [PATCH 4/4] run `cargo fmt`

---
 crates/reporting/src/error/parse.rs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/crates/reporting/src/error/parse.rs b/crates/reporting/src/error/parse.rs
index e099dc87fc..8da55ccc68 100644
--- a/crates/reporting/src/error/parse.rs
+++ b/crates/reporting/src/error/parse.rs
@@ -290,10 +290,12 @@ fn to_expr_report<'a>(
                                 ])
                                 .indent(4),
                             alloc.reflow("And to define a function:"),
-                            alloc.vcat(vec![
-                                alloc.text("increment : I64 -> I64"),
-                                alloc.text("increment = \\n -> n + 1"),
-                            ]).indent(4)
+                            alloc
+                                .vcat(vec![
+                                    alloc.text("increment : I64 -> I64"),
+                                    alloc.text("increment = \\n -> n + 1"),
+                                ])
+                                .indent(4),
                         ])]
                     }
                 },